USB-1808X-OEM User's Guide
Specifications
21
Analog input/output calibration
Table 9. Analog I/O calibration specifications
Parameter
Specification
Warm-up time
15 minutes recommended min
Calibration method
Factory calibration
Calibration interval
1 year
Digital input/output
Table 10. Digital I/O specifications
Parameter
Specification
Digital type
CMOS
Number of I/O
4
Configuration
Each bit may be configured as input (power on default) or output
Pull-up configuration
The port has 47
kΩ resistors configurable as pull
-up or pull-down (default) via internal
jumper (DIO).
Digital I/O transfer rate
(system-paced, asynchronous)
33 to 8,000 port reads/writes or single bit reads/writes per second typ,
system dependent.
Digital I/O transfer rate
(synchronous)
0.023 Hz to 200 kHz input, 500 kHz output, based on the internal clock speed of
100 MHz
Scan clock source for input
Internal input scan clock or external input scan clock (ICLKI pin)
Scan clock source for input
Internal output scan clock or external output scan clock (OCLKI pin)
Trigger source
ITRIG for inputs, OTRIG for outputs (see
Digital pattern detection for inputs and outputs (see
on page 24)
Input high voltage
2.0 V min
5.5 V absolute max
Input low voltage
0.8 V max
–0.5 V absolute min
0 V recommended min
Output high voltage
4.4 V min (IOH = –50 µA)
3.76 V min (IOH = –2.5 mA)
Output low voltage
0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 2.5 mA)
Output current
±2.5 mA max
